There are no structural differences in terms of grammatical relations: in all cases, the participial phrase adjectivally modifies the noun 'mother'. I would note only that

1. #1 is poorly punctuated: the comma is needed before 'weeping' since the participial phrase that it introduces is nonrestrictive (i.e. just like a nonrestrictive relative clause, it supplies incidental, rather than distinguishing, information about the referent).

2. The preposing of the phrase in #3 serves, to a certain extent, to emphasize the participial phrase.

Alan wrote:There are no structural differences in terms of grammatical relations: in all cases, the participial phrase adjectivally modifies the noun 'mother'. I would note only that

1. #1 is poorly punctuated: the comma is needed before 'weeping' since the participial phrase that it introduces is nonrestrictive (i.e. just like a nonrestrictive relative clause, it supplies incidental, rather than distinguishing, information about the referent).

2. The preposing of the phrase in #3 serves, to a certain extent, to emphasize the participial phrase.

Q : Could you show me examples of "distinguishing, information about the referent" ?

He said that since he did not know specifically who was threatening him, he thought it would be fruitless to seek help from the police. "I don't want to go to the cops, who might not know what a hacker is," he said.

Well, it's probably easiest to start with relative clauses, since the principle is identical: if we compare the following sentences,

[1] Peter is the boy that's wearing red shorts.

[2] This is Peter, who's my eldest son.

and compare the italicized relative clauses, we find that the first supplies information that is essential to precisely identifying the referent - in this case, identifying the boy in question as Peter. If we were now to remove that clause, leaving

[1a] ?Peter is the boy.

we would have a, not strictly ungrammatical, but very strange sentence, which would leave the addressee wondering just what was meant by 'the boy'.

The clause of [2], on the other hand, can be removed perfectly well without leaving a strange or incomplete-sounding sentence:

[2a] This is Peter.

The fact that Peter is my eldest son is an additional, but hardly vital, piece of information that is simply 'tacked on', so to speak, just as if I were saying

[2b] This is Peter, and - by the way - he's my eldest son.

We distinguish between these two types of relative clause by labelling the first a RESTRICTIVE (sometimes also called 'defining'), and the second a NONRESTRICTIVE (also termed 'descriptive') clause.

Orthographically the two types can be distinguished in that nonrestrictive clauses are always preceded by a comma while restrictive never are.

Syntactically, they are different in that nonrestrictive clauses may not be introduced by 'that', while restrictive may (and most commonly are).

In the same way, regarding participial phrases, we can discern restrictive and nonrestrictive types, similarly distinguishable by the presence or lack of commas, so that the part. phr. of

[3] Mary is the girl wearing the pink dress.

would be classified as restrictive, being equivalent to the relative clause of

[3a] Mary is the girl THAT's wearing the pink dress.

, while that of

[4] Mary, wearing a pink dress, then entered the room.

would be classified as nonrestrictive, being equivalent to the relative clause of

That's great Thank you for your teaching. I need to read more reading stuffs , because just "knowing it" is totally different with "using it". Whenenver I find a ambiguous thing relative with this topic, I'll post a question this section.

p.s : Do you think I use right English? I want to ask you about my English-language ability. Am I doing well?

Well, I would be lying if I said that your English was faultless, but you generally manage to communicate your thoughts and ideas well on what are often complex and intricate points of language use, clearly a much more difficult undertaking than a conversation about the weather...